In a 6-quart pot combine sugar and 7 cups water; bring to a boil and stir until sugar dissolves. Remove from heat and stir in tea powder while hot. Add orange juice concentrate, lemonade concentrate, and 2 cups cold water. Chill in the refrigerator.

When cold mix in vodka. Pour into a plastic container leaving room on top for expansion. Freeze for 24 hours.

To serve, scoop about 1 cup into a tall glass and quickly stir in 1/3 cup lemon-lime soda.